Electric power companies supply hot water for district heating by using waste heat of a gas turbine or supply high-pressure steam or low-pressure stream for a factory. Petrochemical companies are operating the gas turbine, and the like as power facilities. In various plants or facilities using the gas turbine, and the like, preventive maintenance that detects malfunctions in the facilities or indications thereof is very important to even minimally suppress damages to a society. Further, an anomaly diagnosis that describes an anomaly phenomenon as well as the detection is also important to take appropriate actions.
In addition to the gas turbine or a stream turbine, even in a turbine in a hydroelectric plant, a nuclear reactor in a nuclear power plant, a windmill of a wind power plant, an engine of an aircraft or a heavy machine, a railroad vehicle or a track, an escalator, an elevator, and an apparatus/component level, facilities requiring the preventive maintenance such as the deterioration/lifespan of mounted batteries are numerous. In recent years, detecting anomalies (various symptoms) for a human body becomes also important for health management as shown in an electroencephalogram measurement/diagnosis.
As a result, U.S. Pat. No. 6,952,662 (Patent Literature 1) or U.S. Pat. No. 6,975,962 (Patent Literature 2) discloses an anomaly detecting method primarily targeting an engine.
In the anomaly detecting method, with past data, i.e., a time-series sensor signal as a database, the similarity between observational data and past learning data is calculated in an independent method and an estimate value is computed by linear coupling of data having high similarity to output a displacement degree between the estimate value and the observational data.
Further, Japanese Patent No. 3,631,118 discloses an anomaly diagnosing method of evaluating the similarity between input data and case data with the case data registered as the database and outputting a predetermined event name corresponding to a case having the highest similarity in advance.